Different types of push-in fasteners are known for use in different environments and for different purposes. A known feature of push-in fasteners is a resiliently bendable or deflectable retention member that bends inwardly when the fastener is inserted into an opening and rebounds outwardly to hold the fastener when the fastener is fully inserted. Inward bending of the retention member can be caused by the sliding engagement of the member against the aperture surface in the component. Fastener clips using two or more such retention members are known.
U.S. Pat. No. 5,301,396 discloses a fastener clip assembly with a compression member. The fastener clip assembly includes a fastener having a shank with a head at one end of the shank, with the shank comprising a plurality of resilient legs integrally formed with the head and mutually connected opposite the head at a distal end of the fastener. The legs are bowed outwardly to define a maximum diameter larger than an aperture size in a panel or component through which the fastener is inserted. During installation of the fastener, the legs deflect inwardly so as to pass through the aperture and then rebound outwardly as the maximum diameter portion passes through the aperture. The fastener clip assembly further includes a compression ring having a central tapered aperture with a diameter slightly less than the diameter of the aperture in the panel or component through which the fastener is inserted. When used as a part of the fastener clip assembly, the ring rests against the panel or component through which the fastener is inserted as the fastener is inserted. The ring provides contact against the legs, compressing the legs for passing through both the ring and the panel or component. The slightly smaller diameter of the aperture in the ring holds the legs away from contact with the edge of the aperture. Accordingly, the ring is useful in reducing drag or abrasion that may occur if the aperture of the panel or component is harsh or abrasive to the material of the fastener. The ring and fastener can be made of materials and shaped in a manner so as to slide easily against each other, thereby reducing insertion force required when compared to the force required if the legs were to slide directly against the aperture of the panel or component in which the fastener is used.
The aforedescribed fastener clip assembly has been used effectively to reduce insertion force even with fasteners that provide high retention by having a relatively high extraction force requirement to remove the fastener. If a seal against fluid infiltration is required, a separate, discrete sealing ring is added to the fastener assembly. This additional step can be time consuming and costly.
An occasional problem of known fastener assemblies is that, although the compression ring can be cast together with the fastener, the compression ring is molded at the end or tip of the fastener and must be separated from the fastener and properly positioned on the fastener prior to actual use. The separated compression ring is placed in a so-called “pre-drive” position on the fastener. Although the fastener and compression ring are designed for the compression ring to be held on the fastener in the pre-drive position, during subsequent handling it can happen that the compression ring becomes separated from the fastener. In a large container of fastener assemblies, a dislodged compression ring can be difficult to locate. Locating and repositioning the compression ring on a fastener can be time consuming.